Four-Point Contact Ball Bearings

Specifications

How to choose Rolling Bearings

Points to check when selecting, with the values for this product (Four-Point Contact Ball Bearings).

1. 1. Bore and housing bore dimensions

   This product: Inner diameter d 15 to 95 mm

   Select the bore diameter d to match the shaft seat, the outside diameter D to match the housing bore, and the width B to suit the installation space. Main dimensions are standardized in ISO and JIS dimension series, so interchangeable products can be found by boundary dimension designation. For tapered roller bearings, also check the assembled width T; for thrust bearings, also check the height H.

2. 2. Dynamic load rating based on life calculation

   This product: Basic dynamic load rating Cr 8.3 to 305 kN

   The basic dynamic load rating Cr is the reference value for calculating rated life. Verify that the required life is met using the equivalent load during operation and the rotational speed. For ball bearings, life is proportional to the cube of the load ratio, so providing load margin greatly extends life.

3. 3. Margin for static and shock loads

   The basic static load rating C0r is the allowable standard for permanent deformation generated at the rolling elements and raceways under stationary or low-speed conditions. For applications with oscillating motion or shock loads, confirm that a static safety factor against the maximum load is secured using C0r.

4. 4. Operating speed and lubrication method

   The limiting speed differs by lubrication method, and separate values are given for grease lubrication and oil lubrication. Confirm that the normal operating speed does not exceed the limiting value, and in high-speed ranges also consider cage material and precision grade. The reference speed can also be consulted as a thermal guideline.

5. 5. Precision grade and internal clearance

   Precision grades (P0, P6, P5, etc.) indicate rotational accuracy and dimensional accuracy; for high-precision applications such as machine tool spindles, select higher grades. Internal clearance (C2, CN, C3, etc.) is selected to allow for changes caused by interference fit and temperature differences during operation.

6. 6. Materials and lubrication suited to the environment

   For corrosive, high-temperature, vacuum, or clean environments, select specifications such as rings and rolling elements made of stainless steel or ceramics, or solid lubricants and fluorine grease for vacuum use. Check the operating temperature range, low dust generation, and whether food-grade grease registration applies against the application conditions.

This guide was written by AI based on the listed products' documents and specification items.

About Rolling Bearings and all products

Description

Dimension table for four-point contact ball bearings with bore diameters of 15 to 95 mm. Model numbers are listed for both locating groove and non-groove types. Some bearings are SKF Explorer bearings.

FAQ

Q. What are the bore diameter, outside diameter, and width ranges for four-point contact ball bearings QJ 202 N2MA to QJ 319 N2MA?

A. Bore diameter d is 15 to 95 mm, outside diameter D is 35 to 200 mm, and width B is 11 to 45 mm.

Q. What is the basic dynamic load rating of four-point contact ball bearings QJ 202 N2MA to QJ 319 N2MA?

A. The basic dynamic load rating Cr is 8.3 to 305 kN.

Q. Are four-point contact ball bearings QJ 202 N2MA to QJ 319 N2MA available with and without a locating groove?

A. Yes, both locating groove and non-groove model numbers are available. The dimension table lists both model numbers.

Q. Are there any SKF Explorer bearings among four-point contact ball bearings QJ 202 N2MA to QJ 319 N2MA?

A. Some model numbers are SKF Explorer bearings.

Written by AI based on the content of the source documents.

Source documents

• Catalog アンギュラ玉軸受 (SKF 製品カタログ抜粋) 62 pages Open page 61
  Found on: https://azuma-eg.com/catalogue/